The days of farmers independently operating small family farms profitably are, for the most part, a distant memory. Today's successful farmers rely heavily on quantity, quality and efficiency to operate their businesses successfully. In the hog industry, for example, a successful business operation may include hundreds, if not thousands, of hogs. In such an operation, overhead is kept low by employing only a handful of people to perform all aspects of the maintenance of the hogs, including breeding, feeding, treating, and selling.
The recognized need to increase efficiency in the hog production industry has given rise to the development of numerous devices for assisting hog farming operations. Computers are heavily used to track information related to genetics, feed consumption, and environmental factors, often providing feedback information concerning the quality of the final product. Such feedback allows a farmer to modify production processes for better outcomes. The efforts of farmers to increase profitability and productivity have also been assisted by both the pharmaceutical and nutrition industries. Each of these industries has produced a vast array of nutrition supplements and medicinal regimens to keep hogs healthier and, ultimately, more valuable. The negative aspect of these new regimens is that they require increased man-hours to administer. For instance, it is not uncommon for each hog in a herd to require 7-9 medicinal injections per year--which is nearly double the number required only a decade ago. In today's hog farming environment, both the number of injections per hog and the number of hogs in a typical operation are increasing at the same time the number of employees on hand to maintain the hogs is decreasing. Thus, the maximization of personnel resources and delivery methods becomes ever more critical.
Aside from sheer volume, the delivery of injectable medicines to animals is complicated by the temperaments and behavior of the animals themselves. As a rule, hogs are generally not pleased at the prospect of receiving injections. Furthermore, there is no practical way to restrict movement of the hogs during the injection process. As a result, a hog who is about to receive or has received his medicine may be difficult to control and may intermingle with hogs who have not yet been injected. Accordingly, the possibility exists that certain hogs may go without their intended injections while others mistakenly receive multiple doses. Either scenario--leaving an animal unvaccinated or overvaccinating an animal carry significant downfalls. Such mistakes in the administration of medicines could, in one extreme, threaten the well-being of the animals. In another extreme, the result may be toxic levels of medicines in the end products.
Various methods and devices have been developed to combat these inefficiencies, although recent changes to industry standards and production methods for hogs have rendered many of these solutions obsolete. For instance, as recently as twenty years ago it was a standard practice for farmers to deliver injectable medicines without paying particular attention to the specific location of the injections, either on the hogs or relative to one another. Subsequent research has indicated that this practice resulted in problems such as the delivery of medicines to areas to which they were not optimally assimilated into the bloodstream of the hog. Just as bad, delivery of the medicines to a disadvantageous location could blemish or damage the surrounding tissue, thereby devaluating the final meat product.
A good example of an early medicine delivery device which manifested the above referenced problems can be found in U.S. Pat. No. 3,949,746 (the '746 patent) issued to Wallach. The medicine delivery device of the '746 patent comprises a hypodermic syringe apparatus and includes a contact member having an apertured front plate and a hydraulic cylinder reciprocated mounting plate supporting a group of hypodermic needles in slidable registry with the front plate openings. The needles pierce a liquid absorbing web backing the front plate. Each needle is connected by a flexible tube to an adjustable stroke piston pump and then to liquid injectable holding receptacles. The pistons are simultaneously actuated by a motor driven cam carrying shaft. The motor is controlled by a handle carried switch to rotate the shaft one turn. The shaft carrying cam also controls the flow of the liquid to the handle cylinder, and the absorbent pad is connected to a source of antiseptic. A marking pad is carried by the handle front wall to identify the puncture area.
Because of the complicated nature and resulting expense of the device of the '746 patent, it never found widespread use in the livestock industry, where profit margins are typically too low to support either the purchase or the continued maintenance required by such a complicated device. Additionally, the manner in which the injections are delivered by the '746 patent is now considered unacceptable for several reasons. First, livestock experts now agree that delivering a large number of treatments in essentially the same location may limit the effectiveness of some medicines and may even be detrimental to the animal. Secondly, the former practice of delivering injectable treatments to "high yield" meat areas such as the rump (as shown in the '746 patent) reduces the quality of the salable meat from that area and reduces the profitability of the animal.
More recently, individual syringes have been developed which allow the farmer to apply an injection in any desired location using a single-handled manual syringe. One such syringe is the ST5 "Easy Vac" Automatic Syringe, manufactured by Forlong & Massey d/b/a Simcro Tech of New Zealand and distributed in the United States by Vac-Pac Incorporated of Marietta, Ga. (1-800-793-1671). Typically, the Easy-Vac syringe is used in conjunction with a so-called "paint stick". In livestock operations, the paint stick is a well known device which resembles a large grease pencil and is used to mark the hog which has received the injection. If used properly, the farmer injects the animal with a syringe held in one hand and marks the injected on the animal with a paint stick held in the other hand. Proper use of the paint stick identifies the animal as one which has been injected and, if used properly, may also provide a visible indication of the general location of the injection, although there is no assurance that a mark made by a paint stick has been placed in proximity to the location of the injection. Not only are these benefits helpful in the delivery of future injections, but they serve as the basis for a "quality review" of injection locations by a supervisor whose duty it is to insure that injections are being administered to the proper locations.
Even this improved method of delivering injections poses serious problems for the farmer. First, it is extremely easy for a low-paid manual laborer who is delivering the injections to take a shortcut by injecting the animal in an easily accessible but improper area (such as the rump), then use the paint stick to mark the animal where the injection should have been given, such as in the neck. Secondly, even if used properly, both of the hands of the farmer are occupied, making it extremely difficult to control the animal in any meaningful way. Often, an animal will escape control of the farmer after being injected and before being marked, resulting in the potential risk of an animal receiving multiple injections.
Accordingly, a need exists for an apparatus for injecting hogs and other livestock which delivers injections easily, accurately and reliably. There is an additional need for such an apparatus which will mark both the animal injected and the location of the injection on the animal concurrent with the delivery of the injection. Finally, there exists a need for such an apparatus which can be operated with one hand, leaving the farmer one hand free to control the animal, protect himself or deliver a second injection and mark with a second apparatus substantially simultaneously.